c - Scanf 不等待输入

Question

我有一个问题。当我运行它时，它只是垃圾邮件“更大”，而不是让我写入 scanf。有人可以尝试解释一下原因以及我可以采取哪些措施来解决它吗？

#include <stdio.h>
#include <time.h>

int main(){
    int rn, n=0;
    rn=rand();
    while (n!=rn){
        scanf("%n", &n);
        if (n<rn)
            printf("\nBigger\n");
        else if (n>rn)
            printf("\nSmaller\n");
    }
    printf("\nCorrect\n");
}

Answer 1

%n 不正确。您可能需要 %d 并且应该检查 scanf() 返回的内容以检查是否有错误。

来自man scanf:

 n     Nothing is expected; instead, the number of characters consumed
       thus far from the input is stored through the next pointer, which
       must be a pointer to int.  This is not a conversion, although it
       can be suppressed with the * flag.